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Data Set ID:

Cosmogenic Radionuclides in the Siple Dome A Ice Core, Version 1

This data set includes a record of cosmogenic radionuclide concentrations in the Siple Dome A ice core collected as part of the West Antarctic ice core program. The investigators measured profiles of both 10Be (half-life = 1.5x106 years) and 36Cl (half-life = 3.0x105 years) in the entire ice core, which spans the time period from the present to about 100,000 years before present. These data are being used for perfecting the ice core chronology, deducing the history of solar activity, deducing the history of variations in the geomagnetic field, and studying the possible role of solar variations on climate.

Data are distributed as a PDF file and are available via FTP.

Geographic Coverage

Spatial Coverage:
  • N: -81.6588, S: -81.6588, E: -148.812, W: -148.812

Spatial Resolution: Not Specified
Temporal Coverage: Not specified
Temporal Resolution: Not specified
  • Ice Core Records > Isotopes > Beryllium-10
  • Ice Core Records > Isotopes > Chlorine-36
  • Glaciers/Ice Sheets > Ice Sheets > Cosmogenic Radionuclides
  • Snow/Ice > Snow/Ice Chemistry > Cosmogenic Radionuclides
  • Snow/Ice > Snow/Ice Chemistry
Data Format(s):
  • PDF
Version: V1
Data Contributor(s): K. Nishiizumi, R. Finkel

Data Citation

As a condition of using these data, you must cite the use of this data set using the following citation. For more information, see our Use and Copyright Web page.

Nishiizumi, K. and R. C. Finkel. 2007. Cosmogenic Radionuclides in the Siple Dome A Ice Core, Version 1. [Indicate subset used]. Boulder, Colorado USA. NSIDC: National Snow and Ice Data Center. doi: [Date Accessed].

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Detailed Data Description

File and Directory Structure

The file SD-10Be_Report.pdf contains data for 10Be organized into five columns representing the following information.

Top (m) Sample distance from the top of the core
Bottom(m) Sample distance from the bottom of the core
Length (m) Sample length
Solution Mass (g) Mass of 10Be in the sample
10Be (atom/g) Concentration of 10Be

The file SD-36Cl_Report.pdf contains data for 36Cl organized into 11 columns representing the following information.

ID Sample identification
Top (m) Sample distance from the top of the core
Bottom(m) Sample distance from the bottom of the core
Length (m) Sample length
Solution Mass (g) Mass of 36Cl in the sample
Cl Carrier (mg) Mass of Cl carrier
Cl in ice (ppb) Concentration of Cl in ice
36Cl/Cl (atom/atom) Ratio of 36Cl to Cl
±36Cl/Cl (atom/atom) Ratio of ±36Cl to Cl
36Cl (atom/g) Concentration of 36Cl
±36Cl (atom/g) Concentration of ±36Cl
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Spatial Coverage

Southernmost Latitude: 81.6588° S
Northernmost Latitude: 81.6588° S
Westernmost Longitude: 148.8120° W
Easternmost Longitude: 148.8120° W

Spatial Resolution

The top of Siple Dome A ice core was 0.377 m in depth and the bottom was 1003.809 m in depth. The core has a diameter of 13.3 cm. Investigators collected samples at variable intervals and depths.

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Temporal Coverage

Data represent a time span of approximately 100,000 years before present. The Siple Dome A ice core was drilled on 9 January 1997.

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Parameter or Variable

Cosmogenic radionuclides in polar ice cores have been used to study the long-term variations in several important geophysical variables, including solar activity, geomagnetic field strength, atmospheric circulation, snow accumulation rates, and others. The investigators will use cosmogenic radionuclide concentrations to study climate history through the effects of atmospheric circulation and of atmospheric chemistry on nuclide deposition.

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Data Acquisition and Processing

Data Acquisition Methods

All data were obtained after melting the ice, filtration, anion exchange chromatograph, cation exchange chromatograph, chemical separations, purifications, and AMS.

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Quality Assessment

These are preliminary data of cosmogenic radionuclides (10Be and 36Cl) in the Siple Dome A ice core. Depths are at variable intervals and are not continuous. Investigators have provided 36Cl/Cl ratios. Calculation of 36Cl concentration (atom/g) requires the Cl concentration in the same sample, which is not available. All 10Be results have more than 20% uncertainty due to accelerator mass spectrometry (AMS) calibration issues and the uncertainty in the volume of melting water; these require large corrections.

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Sensor or Instrument Description

Investigators carried out chemical measurements at the Lawrence Livermore National Laboratory (LLNL) accelerator mass spectrometry (AMS) facility.

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Contacts and Acknowledgments

Kunihiko Nishiizumi
Space Sciences Laboratory
University of California, Berkeley
7 Gauss Way
Berkeley, CA 94720-7450 USA

Robert Finkel
Lawrence Livermore National Laboratory
PO Box 808 (L-232)
Livermore, CA 94550 USA


This research was supported by the National Science Foundation (NSF) Office of Polar Programs (OPP) grant OPP-0126343.

Document Information

Document Creation Date

May 2007

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